The paper gives results of an experimental determination of the penetration of individual fuel droplets injected into a swirling gas flame, as a function of the droplet injection parameters of spacing, velocity, size, and angle. It also describes additional experiments in cold flow to evaluate the effect of droplet spacing on drag coefficient. Theoretical predictions of a simplified three-dimensional droplet trajectory model compared well to the hot flow experimental observations. It was found that bypassing and penetration of large droplets, which can occur in practical situations, may lead to failures in liquid-fired hazardous waste incinerators. Cold flow studies indicated that the average drag coefficient depended strongly on droplet spacing, for a droplet spacing of less than 150 droplet diameters. Although turbulent fluctuations gave rise to distributions of droplet paths, both their average behavior and their trends with respect to injection variables compared well to trajectory predictions utilizing the experimentally determined mean velocity field.